A cooler contains 9 Cokes and 3 Pepsis If you choose two sod

A cooler contains 9 Cokes and 3 Pepsis. If you choose two sodas (no replacement), find the probability that you will choose:   a) two Cokes b) two Pepsis c) a Coke, then a Pepsi

Solution

a)

P( 2 Cokes) = 9 C 2 / 12 C 2 = 0.5454

b)

P( 2 Pepsi) = 3 C 2 / 12 C 2 = 0.04545

c)
P( a Coke then a Pepsi) = 9/12 * 3/11 = 0.2045